# Dioxin concentrations in Finns

## Question

What are the dioxin concentrations in the Finnish population? Indices used: congener, age, sex, fish consumtion...

## Rationale

The dioxin concentration is a function of the following inputs:

• Actual measured concentrations in two studies: KTL Sarcoma study and WHO mother's milk study. The data are indexed by congener c, individual i, year y, sex s and weight w. Only c and i are marginals in the data.
• Fish intake and other food intake from questionnaires. The data come from KTL sarcoma study. Indices i, food type f (includes fish species). Both i and f are marginals.
• Dioxin concentrations in fish from the study EU-kalat 1&2. Indices f, pooled fish sample p. Both f and p are marginals.
• Dioxin concentrations in food from the Finnish market basket study. Index f, which is marginal.
• ----#: . Check also: Ax E, Lampa E, Lind L, Salihovic S, van Bavel B, Cederholm T, Sjögren P, Lind PM. Circulating levels of environmental contaminants are associated with dietary patterns in older adults. Environ Int. 2015 Feb;75:93-102. doi:10.1016/j.envint.2014.11.008 . Epub 2014 Nov 19. [1] [2] --Jouni (talk) 14:27, 26 January 2015 (UTC) (type: truth; paradigms: science: comment)

This model is based on one-compartment kinetics with a dioxin intake trend (r %/a decrease). For detail, see Human PBPK model for dioxin

The total amount of dioxin Mn from all doses during the follow-up time period, with a possible breast feeding period during the observed time span, is:

$\displaystyle M_n = \frac{d_n}{r-k} (e^{(r-k) t}-1) (1 - (1-e^{-k_B t_B})(e^{-k t_S})),$

The amount of dioxin in the body now (Mn) from doses di at all timepoints i is calculated as follows, if the dose during time decreases at a constant rate r; dose at the current timepoint is dn. k is the elimination constant, t is the length of follow-up time. kB is the elimination constant caused by breast feeding, tB is the duration of breast feeding, and tS is the time since the breast feeding.

dn is estimated based on information about dioxin intake via food:

$\displaystyle d_{n,i,c} = \Sigma_f I_{f,i} c_{f,c} + \Sigma_e I_{e,i} c_{e,c},$

where I is intake (g/d), c is concentration of dioxin, and indices n means timepoint now, i means the studied human individuals, c means dioxin congener, f means fish species, and e means other food items eaten.

### Data

This data is for years 1996-1999, when the sarcoma case control study was performed (Tuomisto et al., 2004). The individuals are only from Southern and Central Finland (south from Vaasa). Based on WHO mother's milk follow-up studies, it has been estimated that the PCDD/F concentrations are decreasing by 5% per year in Finland.

Tuomisto JT, Pekkanen J, Kiviranta H, Tukiainen E, Vartiainen T, Tuomisto J. Soft-tissue sarcoma and dioxin: A case-control study. Int J Cancer. 2004 Mar 1;108(6):893-900.

The result is based on data [3].